There are isekai classics like:
https://www.mangago.zone/read-manga/the_reason_why_raeliana_ended_up_at_the_duke_s_mansion/
https://www.mangago.zone/read-manga/is_it_a_fortune_or_is_it_a_woe/
It's hard to find something completely without magic, but:
As mentioned above I can also recommend this one. It has magic, but the MC's mana sucks, so she dabbles just in the theories, which is basically just some math and it's not explained in depth.
https://www.mangago.zone/read-manga/isn_t_being_a_wicked_woman_much_better/
Souls switch. A magician works for MC, but there's no other magic except for him. This one's a true villainess story, not just a poor kind soul trapped in a villainess body. She can and she will screw over anyone that pisses her off. And smut, a bit at the beginning and then later in the story ^^
https://www.mangago.zone/read-manga/concentration_of_malice_r19_version/
The OG FL is a magician, but the MC isn't, so there are some basics of mana and energies and stuff, but not that much. Highly recommended, very fun to read.
https://www.mangago.zone/read-manga/beware_of_the_villainess/
oh, there's also this one:
https://www.mangago.zone/read-manga/kill_the_villainess/
has a witch, that helps the MC understand what happened to her soul and how to go back, so the witch uses magic, but MC is magicless
Villainess stories with no magic? Other than the isekai aspect if there is one of course
Idk why but everytime magic gets involved i get uninterested bc its like now i have to learn the magic system and all these dumb names and the system is half baked bc magic is just supposed go be a plot device and not actually integrated in the world building, so i want more villainess stories without magic at all